In the communication field in recent years, data rates are becoming higher, since due to an increase in amount of communication data, each signal transmits a large amount of data. Thus, data rates are becoming higher in recent years. High-speed data is highly likely to be degraded due to intersymbol interference or the like occurred in a cable, a board, an output device or the like. An emphasis signal (pre-emphasis signal) that has an emphasized component in which intersymbol interference easily occurs is therefore used in consideration of a component that may be degraded due to a lack of a band in some cases.
As an example of a method for generating the emphasis signal, a finite impulse response (FIR) method for dividing a signal into signals, providing the difference between delays of the divided signals, and adding or subtracting one of the divided signals to or from the other of the divided signal is known (refer to, for example, Japanese Laid-open Patent Publication No. 2004-88693). In addition, a technique for achieving a bandpass filter using an infinite impulse response (IIR) filter in a wireless communication device is known (refer to, for example, Japanese Laid-open Patent Publication No. 2004-88693, and Stefan Andersson, Peter Caputa, and Christer Svensson, “A tuned, inductorless, recursive filter LNA in CMOS”, ESSCIRC2002 Pp. 351-354).
In the aforementioned techniques, however, the degree of emphasis is low, and it is therefore difficult to flexibly shape a signal on the basis of a requested signal waveform.